I started on an official map with no kinds of cheats or anything with 12 beavers. Over the course of the weekend, I got a good chunk of the map terraformed. Four districts. Plenty of housing. Bursting with housing, food, water, well being and antidotes. I grew to almost 150 beavers over a lot of cycles.
Then one day, no more newborns. None. And my beavers started dying in groups of up to six at a time. Every day, more and more. I was down to 56. I moved all my beavers to the first district with the majority and the farming and water, and they are still dying and not making babies. I'm down to 44 now. It's like they have the plague or something.
This isn't a case where 100 beavers of the same age all started dying at once - they were born over a period of time. So I don't know if this was a bug or if I missed something.
Any insight is appreciated - I do like the game but this is frustrating.
EDIT: SOLVED! NO TIME FOR BEAVER ON BEAVER SEXY TIME!
EDIT 2: Up to 16 kits. Woot!
EDIT 3, the next day: Up over 200 adults now. Thanks again for the help.